Detector for misfiring



Patented sepei'ao, 1930 PATENT OFFICE 'WILLIAM L. 'MCLAUGHLN, 0FSEATTLE, WASHINGTON 'DETECTOR FOR MISFIRING Application led September24, 1928. Serial No. QTY-,884.

My present invention relates to improvements in detectors for misringofl spark plugs4 in an internal combustion engine.

The primary object of the. invention is the 5 provision of means wherebyimproper ignition of the cylinders-ot1 the engine may be detected by theuse of an indicator or detector in combination with the spark plug. Theinvention contemplates the use of an indicator located in position whereit is readily visible to the and electrically connected with the sparkplugs oi' the engine. Means are provided on the detector or indicatorwhereby the successive explosions in the cylinders are illustrated by aHash. 0n the' indicator by the utilization of the device of my inventionthe ignition system of the engine may be tested and the voltage of theelectric currents is indicated in order that the driver of an automobilemay be acquainted with the conditions existing in the ignition system. i

My invention consists in certain novel combinations and arrangements ofparts as will hereinafter be more fully set forth and claimed. y

ln the accompanying drawings l h ave illustrated one complete example ofthe physical embodiment of my invention' wherein the parts are combinedand arran ed according to the best mode I have so ar devised for thepractical application of the principles of my invention.

Figure 1 is a Ivievv'showing as much of an automobile and its motor andconnections as is necessary to illustrate the installation of the deviceot' my invention. Figure 2 is an enlarged detail transverse verticalsectional view of the detector. Figure 3 is a plan View of the detectorwith 'the screw cap removed. Figure 4 is a plan view of the ddtector.Figure 5 tional view showin one of the neon gas tubes utilized for iluminating the dial or face of the detector.

In order that the general arrangement an relation of parts may readilybe understo I have shown in Figure 1 a conventional motor M having fourspark plugs VS and the ignition system includes wires W lfrom the driverof an automobile.

number of spark plugs,

vbakelite or other suitable is an enlarged detail sec-n spark 4plugsthat extend through a condenser C, which performs its usual Jfunctions7to the detector which as shown is mounted upon the dashboard D of theautomobile. v

The detector is mounted upon the dash- 5 board and is lprovided with aseries of markers or arrows 1, 2, 3, 4, and astar 5. The arrows aredisposed in circular arrangement about the central star 5 and theseinsignias are fashioned as' slots in the faceplate 6 or 6 dial of thedetector. The dial or faceplate is of opaque material and the arrows are.l

illuminated with the successive firings or explosions in the fourcylinders of the engine. The number of arrows is determined bythe 6 andthe star 5 is illuminated from the ignition circuit byproperconnections, as a pilot light. 'In this manner the'detectordisplays successively the firingof the cylinders, and of course if acylinder misses vfire the arrow is not illuminated. Upon detection of amis-fire in the cylinders the automobile driver may' of course remedythe trouble.

The 4detector includes 8 by means 'of which it is vattached tothedashboard D. and a screw cap 9 in theY shape of a lring isthreaded ontothe cup'7. The

ring or screw cap u as a retaining flange 10 which fits over the dial orface plate 6 and 9 holds it in position. Within the cup is mounted acrucform insulator 11 which may be material. The insulating block 11` isprovided with angular notches 12 in. its edge and these notches co-act 8with the radial, centering lugs 13 that projectl inwardly from the rimof the cup into saidl notches. By this means the insulating block 11 iscentered and retained in the cup, and the cap ring 9 holds the parts inplace.

The insulating block series of. arcuate rooves 14 in its face, thegrooves being pro ided with open ends, and, the, block valso has acentral groove 14. Within these lgrooves are secured comple- 9 mentarytubes 15 preferably of glass and filled with neon gas. It will beunderstood that when the gas is charged with'an electric current or.when the current passes through the gas in the tube, the tube isilluminated, l

a cup 7 having lugs 75 1s provided with a y not pass through the andasthe tubes are located behind the arrows and star of the dial, it will beobvious that the through the gas in the tubes will illuminate thedetector signals of the dial or face plate. The neon tube is normallyilluminated with a color` as pink, light, and the depth of the colorindicates the voltage of the current of electricity passingtherethrough. If a spark plug is mis-firing, the current ofcourse doesgas tube, an d the arrow is not illuminated.

The wires W are connected to the ends of the gas tubes by the employmentof steel wool packing 16 which packing forms a conductor for theelect-'ric current and the wires from the condensers and spark plugs are`brought. to the detector through a hollow boss in the back of the cup 7as indicated at 17. I y

Having thus fully described my invention, what .I claim as new anddesire to secure by Letters Patent is: i

l. The combination in a detector with a eup having an insulating blocktherein and (fo-acting retaining mcans on the cup and block, of aplurality of gas tubes mounted in said block and electrical wiresconnected to said tubes, a dial having slots complementary to saidtubes, and a screw cap for the cup having means for retaining said dial.

2. T he combination in a detector with a cup .and aninsulating blocktherein, of radial lugs on said cup engaging notches in the block. saidblock having arcuate grooves and neon gas tubes in said grooves,electrical connections to said tubes and dial having slotscorresl'iomling to said tubes, a screw cap for the cup and a yretainingring on said cap.

1n testimony whcrcoi' l atix in v signature.

VILLIAM L. MCLAUGHLIN.

current of electricity passing"

